1. The Field of the Invention
The present invention relates generally to a drill and method for extracting bone grafts. More specifically, the present invention relates to removing bone graft material from a patient using a combination drill bit and guide.
2. State of the Art
In the course of a variety of surgeries, it becomes necessary to graft bone from one part of the body to another in an effort to strengthen bones that have had operations. For example, bone grafting is very common in orthopedic surgery, neuro/spine surgery, and plastic surgery. Several bone graft products are commercially available and usually depend on bone harvested from cadaver donors (allograft bone). However, processing of cadaver bone may have deleterious effects on the biological properties of the bone products. Allografts are only osteoconductive, and they involve considerable cost, pose the risk of disease transmission, and are objectionable to certain religious groups.
Autologous bone grafts are harvested directly from the patient and are considered to be the “gold standard,” because they are inherently biocompatible, osteoconductive, osteoinductive, and osteogenic. Harvesting autologous bone is usually carried out by taking bone from a part of the patient's body other than the surgical site. This results in additional surgical time and the additional surgical harvest has its own attendant risk of complications, such as donor site pain and morbidity. The major disadvantage of autograft bone is that it requires harvesting of bone from a separate donor site which prolongs surgical time and creates donor site morbidity. Many patients complain that the pain associated with the donor site is greater than that of the primary operative site. The iliac crest of the pelvis is a common donor site, and one current method for harvesting bone from the iliac crest includes using a trephine device to take a core sample of bone.
It is advantageous to have a technique for harvesting bone from the iliac crest of the pelvis (a very common donor site) in a way that limits donor site pain, speeds the harvesting process, and provides adequate bone volume for a variety of surgical needs.